Right, so I've spent many hours trying to find the best composition to even do decently in this mod, and I think I've found something that works somewhat well in combat. This is only for combat, mind, so it won't take into account thievery or anything like that. Let's first take some matters into account;

1) Rangers are currently useless due to the incredibly low damage from Snipe and the scarcity of good weapons.

2) Smarter combat AI can now actually utilize their superior everything to crush you, if you're not careful and just rush into them when you're lower level than they are, like was possible in previous patches.

3) Survivability is an issue; lack of decent gear and price hell with merchants makes getting your armor ratings high really hard.

So, here's how I made my game a BIT easier.

Party Composition

2 melee tanks (1 Knight + 1 Fighter is what I did)
2 mages (all elements, so an Enchanter and a Wizard seem to work fine)

I suggest making one of the mages (the Enchanter) as your player character, and picking Armor of Frost for one of his/her starting skills. Since it's unlikely that you will get that skill during the game, it's infinitely better to start with it. Fighters are necessary due to their Fortify ability and tankiness. MA and PA are vital to the survival of your party.


Strategy

Your general idea of "how to strategy" with this composition is simple. Ground effects, ground effects and ground effects. You milk the shit out of ground effects and you don't care if it hits your own tanks as well. They should have their armours up regardless. Just remember: if it damages the NPC, it's good.

In short, this build is based around heavy tank + heavy CC.

Let your mages hang far back and put your melee characters in front; space them away from each other so that they won't get caught in the same CC. Buff the Knight with Armor of Frost. ALWAYS open the fight with your mages. Fossil Strike / Rain into a group of enemies, followed by Searing Daggers or Electric Discharge. I've found that stunning enemies with rain + aerotheurge spells is better if you're in a pinch, whereas FS + SD is better for opening fights.

Once your melee characters are in range, have your Fighter cast Contamination and engage the biggest, toughest NPC. Your Knight will move closer to the Fighter now, and your aim is to 1) get the NPCs PAs low and 2) use Cripple on as many of them as possible.

Tip: have Red Prince be the Knight! He's a great tool with his Dragon's Blaze racial ability to just light up any oil surfaces your enemies are standing in. A strategy I always found satisfying was sneaking up to the always abundant oil barrels, placing them into a chokepoint and then luring in all of the enemies who, naturally, will go and stand next to it. Then just Armor of Frost your tank and cast Dragon's Blaze. BOOM!

Useful skills to have Vital; Recommended; Situational

Armor of Frost
Fortify
Rain + ED / FS + SD


Teleportation (save it for teleporting their melees back to your own melees)
Battle Stomp
Crippling Blow
Haste


Rage
Battering Ram (this does damage and knocks down, yes, but it also gets your fighters out of position as you don't engage with your melees. Battle Stomp is a better alternative to this, but BR can also have its uses.
Hail Strike (can be useful when coupled with Rain, but its high AP cost makes it only situational. ED is a better alternative.

Don't take this as gospel or anything; I'm basing this guide on my own experiences as a player and what has worked for me. Even this composition didn't get met out of some bad situations. Still, I wanted to share this, see what people think, if it works for them or not. It's probably futile to make posts like this for alpha versions, but I do it with the hope that someone will find it useful in tackling the challenges of this current version.